My furnace stopped working last Saturday so I started troubleshooting to find the problem. I found that the board was not providing 110V to my inducer motor. So I determined that I needed a new board. I called a furnace expert to verify my troubleshooting and they discovered that the inducer motor was pulling ~4uA so it needed replaced too. I ordered the parts and replace them. My furnace now works however it is short cycling. Sometimes for just a couple minutes the flame will turn off and they system shut down even though the house is still ~10-15 degrees lower than the set point. Other times it will run for ~10 minutes before this happens. The furnace tries to come back on but never does. I have clean and check the flame sensor to make sure it is pulling the right amount of current and it only shut off after the flame went out. I also check the pressure value and it also only closes after the inducer motor stops. The air filter is new so I don’t really know what else it could be.
The Furnace is ~15 years old and is a Lennox brand.